It has been typically known to detect possibility of occurrence of an accident such as an overturn in a combination vehicle including a front vehicle body having a cab and a rear vehicle body having a cargo bay and the like, the front vehicle body and the rear vehicle body being connected with each other (see, for instance, Patent Literatures 1, 2).
A combination vehicle (e.g. trailer truck) disclosed in Patent Literature 1 includes: a towing portion; a towed portion; a towing-portion sensor provided on the towing portion; towed-portion sensor provided on the towed portion; one or more steering sensor; one or more environmental sensor; one or more wheel speed sensor; and a processing device that analyzes the data received by the sensors. At this time, the processing device: compares a first threshold with a difference between a towing-portion yawing speed detected by the towing-portion sensor and a towing-portion yawing speed intended by an operator based on the data from the steering sensor; compares a second threshold with a difference between a towed-portion yawing speed detected by the towed-portion sensor and a towed-portion yawing speed intended by the operator based on the data from the steering sensor; compares a third threshold with a difference between towed-portion yawing speed and the towing-portion yawing speed; judges whether or not a correction control is necessary based on the results of the comparisons; and judges which one of correction controls should used based on the differences in the above three calculation results.
Further, the processing device determines the correction control to be started based on the data including the towing-portion yawing speed, the towed-portion yawing speed, towing-portion lateral acceleration, towed-portion lateral acceleration and the wheel speed sensor.
Patent Literature 2 discloses a rollover-prevention device for preventing rollover of vehicles such as bus, truck and tractor-trailer combination vehicle. A first rollover-prevention device disclosed in Patent Literature 2 calculates a roll status of the vehicle based on a data inputted through a switch for selecting a wheel base of the vehicle and a switch for selecting steering gear ratio, and signals from various sensors including roll angle sensor for detecting a roll angle of a vehicle body; a steering-angle sensor and vehicle speed sensor. The first rollover-prevention device issues a rolling danger warning information and alarms an operator with an alarm buzzer.
Further, a second rollover-prevention device calculates a roll status of the vehicle based on a data from a roll angle detector for detecting a roll angle of a vehicle body and a lateral G sensor for detecting lateral acceleration of the vehicle body. The second rollover-prevention device issues a rolling danger warning information and alarms an operator with an alarm buzzer.